Robust regeneration of tissues and complex organs is the norm for countless invertebrate and nonmammalian vertebrate species. In addition, nature has endowed certain animals with remarkable longevity and robust tissue repair mechanisms that slow aging-induced degenerative processes, or with increased susceptibility to cellular and molecular damage and concomitantly short lifespans. Numerous fundamental questions in regenerative biology can only be answered in vivo using diverse non-mammalian animal models. In addition, comparative studies of diverse organisms provide deeper mechanistic insights that are not possible using a single model or model-centric approach, and they can speed the pace and reduce the cost of biomedical discovery. The Comparative Animal Models Core builds on MDIBL's unique strength and expertise in comparative animal biology and will provide COBRE investigators with resources necessary to utilize diverse animal models in regenerative and aging biology research. For the current application, the Core focuses primarily on providing resources and services to COBRE Project Leaders for their proposed zebrafish studies. These resources include day-to-day husbandry, importation and quarantine services, spawning services to produce embryos for experimental studies, microinjection and surgical services, drug treatment services and genotyping using visual inspection and PCR-based methods. The Core will also have both the facilities and expertise necessary to provide COBRE associated investigators as well as potential new COBRE Project Leaders with resources for other vertebrate and invertebrate model systems useful in regenerative and aging biology research including C. elegans, amphibians and various fish species. Our long term goal is to develop the Core into a one-of-a-kind animal resource by leveraging the scientific background and expertise of the Core Director, his staff and MDIBL's faculty, as well as MDIBL's 113-year history of providing and maintaining diverse marine organisms for biomedical research. The Comparative Animal Models Core will thus contribute not only to the success and long term sustainability of the COBRE, but also to the success and continued growth of MDIBL and biomedical research in Maine.